Put the methods in order from highest to lowest according to Oracles order of precedence:
a. Default setting
b. Client environment variable
c. Explicit ALTER SESSION statement
d. Inside SQL function
e. Server initialization parameter
A. b,d,e,a,c
B e,a,b,c,d
C. d,c,b,e,a
D. a,b,d,c,e
E. d,c,b,a,e
答案：（C）
解析：
d优先级最后，默认的优化级肯定最低
SQL->Session->Client->Server(init)->Default